Finish grinding mechanism



July 9, 1940. RABE 2,207,268

- FINISH GRINDING MECHANISM Filed NOV. 26, 1937 \iis Patented July 9, 1940 rnvrsn GRINDING MECHANISM Karl Babe, Stuttgart, Germanyra ssignor to m.

ing. h. c. F. Porsche, K.-G., Stuttgart-Zillionhausen, Germany, a company of Germany Application November 26, 1937, Serial No. 176,563

In Germany November 28, 1936 9 Claims.

This invention relates to a finish grinding mechanism, and more particularly is directed to an arrangement for the finish grinding of cams or other irregular shapes.

An object of my invention is the provision of an economical and simple means for the finish grinding of regular or irregular shapes.

Another object of my invention is the pro-' vision of means for the direct finish grinding of cams or other irregular shapes.

Another object of this invention is the pro vision of means for the finish grinding of cams or other irregular shapes directly from a con trolling diagram.

A more specific object of this invention is the provision of an arrangement for the accurate finish grinding of control cams directly from a valve-lift diagram.

These and other features of the invention willbe best understood and appreciated from the following description of-a preferred embodiment thereof, described for purposes of illustration and shown in the accompanying drawing in which:

, The single figure shows a side elevation partially in cross-section and partially diagrammatically of a preferred arrangement 'for carrying out this invention.

As indicated in the drawing, I preferably provide a pair of bearings l0 and II for journaling a shaft 12, to one end of which is connected by any suitable means a disk |3. A handle ll is provided on the disk ii for rotating the said disk together with the shaft I2. The latter is preferably threaded along the major portion of its length and'a nut l5 engages said thread for movement along the shaft. Thenut 15 maybe provided with a bore It for the iournaling oi slides which are slotted to receive the lower end of a forked lever IT. The upper end of the lever V I1 is rigidly attached as by means of a key to a shaft l8 journaled for rotation about a fixed axis in a frame orv other means not shown. A second lever I9 is likewise fixedly attached to the shaft Is at one end, while on its other end the lever i9 has a grinding'wheel 20 journaled for rotation thereon.

It will be seen from a study of the parts indicated above, that upon turning the handle l4 the shaft 12 will rotate in bearings III and II. Such rotation will move the nut l5 longitudinally along the shaft, thereby rotating the lever arm I! about the axis of shaft it. This results in a rotary movement of the lever arm I9 together with the grinding wheel 20, so that as viewed in the drawing, the grinding wheel 2| will move about the axis of the shaft i8. upwardly or downwardly in a vertical plane. As ,thedisk I3 is The grinding wheel 20 adapted to operate upon a suitable work-piece indicated in this case as a cam 22. The cam is adapted to be placed upon a rotatable support 24 and attached thereto in any suitable manner. The support 24 is provided preferably upon its periphery with a plurality of ratchet teeth engaged-by means such as a pawl 23. The pawl 23 is preferably pivoted about -'a fix'ed bearing block 28 and is adapted to be moved by a handle 25 connected to oneend of the pawlthrough a rod 30.. The pawl 23 Has been illustrated as consisting. of a double lever having a spring pressed tooth at one end thereof engaging the ratchet teeth. Asecond pawl 29 is adapted'to engage the ratchet teeth in an opposite sense from that of the pawl 23 in order to prevent reverse movement of the member 24. It will be seen that uponmovement of the handle 25 inwardly, the engaging'endof the pawl 23 will move in, the direction indicated by the arrow to ratchet along the member 24, thereby shifting the position of the work-piece 22 relative to the grinding wheel 20. In order to indicate the number of notches movedthere may be provided a counter 2'IJengaged by, am; 28 on the rod 30, so arranged that upon each inward movement of the rod 30, the counterywill advance one position. It will be seen from the above description that by means of this invention, a simple and accurate grinding of the cam may be brought about. All of the control members are adapted to be positioned so as to be readily handled by one operator who, at the same time, may be accurately adjusting the position of the grinding wheel by examining the scale through the reading microscope. By meansof this arrangement, it is possible to grind cams or 'othershapes directly from a control diagram without the necessity of first forming a control cam by laborious methods.

. The invention has been found to be particularly advantageous ,in the direct transfer of the dimensions of a. valve-lift diagram to the formation of the desired control cam.

It is obvious that myinventiou is not limited to the construction illustrated. Any equivalent linkage means could be utilized for the movement of the grinding wheel. The scale need not be positioned in a plane at right angles to the axis of the shaft, but in any other suitable manner. The rotation of the work-piece could be brought about by means other than the pawl and ratchet illustrated; for example, a worm gearing arrangement could be used. If the pawl and ratchet arrangement is retained, it is also within the comprehension of this invention that the pawl could be actuated electro-magnetically as well as by hand. It is to be understood, therefore, that the scope of this invention is only limited as indicated in the claims which follow I claim:

1. In a grinding mechanism, in combination, a shaft, means for journalling said shaft, threads on said shaft intermediate said journalling means, a nut mounted on said threads for movement along said shaft, an arm pivotally andv slidably connected to said nut at one end and pivotally mounted about a fixed axis at its other end, a second arm mounted for pivotal movement with said first arm about said fixed axis, a grinding wheel rotatablymounted on said second arm, rctatable means adapted to support a'work-piece in operable relation with said grinding wheel, ratchet teeth on said supporting means, a first pawl,

means for actuating said pawl for rotating said supporting means, a second pawl for preventing movement of said supporting means in a direction opposite to that produced by said first pawl,

a scale mounted for rotation with said shaft,

fixed means in co-operative relationship with said scale for determining the position of said grinding wheel, whereby upon movement of said shaft said grinding means may be moved to desired positions as observed upon said scale and said rotatable supporting means may be rotated simultaneously by said pawl means so that said work piece may be ground to any desired contour.

2. The combination according to claim 1, in combination with a counter, and means on the said pawl actuating means for engaging said counter, whereby the relative rotary position of said work supporting means can be determined from said counter.

3. The combination according to claim 1, in combination with means actuated upon rotation of said work supporting means for indicating the position of said work piece.

4. The combination according to claim 1, in which said first pawl is mounted for rotation about a fixed axis, and the means for actuating said pawl comprises a lever pivotally connected to said pawl.

5. In a grinding mechanism, in combination, a shaft, means for journalling said shaft, threads on said shaft intermediate said journalling means, a nut mounted on said threads for movement along said shaft, an arm pivotally and slidably connected to said nut at one end and pivotally mounted about a fixed axis at its other end, a second arm mounted for pivotal movement with said first arm about said fixed axis, a grin'd ing wheel rotatably mounted on said second arm, rotatable means adapted to support a work-piece in operable relation with said grinding wheel, a scale mounted for rotation with said shaft, fixed means in co-operative relationship with said scale for determining the position of said grinding wheel, whereby upon movement of said shaft said grinding means may be moved to desired positions as observed upon said scale and said rotatable supporting means may be rotated simultaneously by said pawl means so that said work piece may be ground to any desired contour.

6. In a machine for producing continuous irregular contours on a work piece, means for sup porting said work piece for rotation about an axis, manually controlled means for at will imparting increments of rotary movement to said work piece about its axis, a material removing tool, a support therefor, manually controlled means for moving said support and tool in and out with respect to said axis, scale means for indicating the position of said tool relative to the axis of said work piece, and an indicator for showing the extent of rotative movement given to said work piece, said work piece rotating means and said tool moving means being movable alternately.

'7. In a machine for producing continuous irregular contours on a work piece, means for supporting said work piece for rotation about an axis, manually controlled means for at will imparting increments of rotary movement to said work piece about its axis, including a ratchet and a pawl drive mechanism, a counter to count and indicate the number of steps the work piece has been rotated, a material removing tool, a support therefor, manually controlled means for moving said support and tool in and out with respect to said axis, and scale means for indicating the position of said tool relative to the axis of said work piece, said work piece rotating means and said tool moving means being movable alternately.

8. In a machine for producing continuous irregular contours on a work piece, means for supporting said work piece for rotation about an axis, manually controlled means for at will imparting increments of rotary movement to said work piece about its axis, including a ratchet and a pawl drive mechanism and a counter to count and indicate the number of times the ratchet and pawl mechanism has been actuated, a material removing tool, a support therefor, manually controlled means for moving said support and tool in and out with respect to said axis, and scale meansfor indicating the position of said tool relative to the axis of said work piece, said work piece rotating means and said tool moving means being movable alternately.

9. In a machine for producing continuous irregular contours on a work piece, means for supporting said work piece for rotation about an axis, manually controlled means for at will impartingincrements of rotary-movement to said work piece about its axis, a material removing tool, a support therefor, manually controlled means for moving said support and tool in and out with respect to "said axi'sj said work piece rotating means and said tool moving means being movable" alternately, and position indicating mechanism on the means for moving the tool and the means for rotating the work piece, whereby a predetermined design .of said work piece may be plotted and followed.

KARL RABE. 

